In cameras of the prior art, film advance and rewind means have been provided for rotating take-up and supply spools to advance and rewind the film. In some cases, a one-way clutch has been provided between the rewind lever or control and the supply spool for the purpose of reducing friction and drag during the film advance operation. For rewind, a release control button or the like has typically been provided for actuation by the user of the camera during operation of the rewind means, the control button being effective to disconnect the take-up spool from the film advance means. Another type of mechanism has also been proposed in which an operating knob is shifted axially between two positions, being operative in one position to rotate the take-up spool and being operative in the other position to rotate the supply spool and rewind the film.
Such prior types of mechanisms have been generally satisfactory but have been subject to malfunctions and have had other problems which have not been recognized by those responsible for the design of the cameras. For example, one problem which has not been recognized and dealt with is that the user of the camera may not realize that it is necessary to operate the release control button or to axially shift a control in order to rewind, especially when first operating the camera or when he operates the camera infrequently and forgets details of its operation from one time to another. If a user improperly operates the camera, he may, of course, damage its mechanism. For example, if he attempts to operate the rewind mechanism without operating the release button, he may damage the advance mechanism and other parts of the camera mechanism connected thereto.
Another aspect of the prior art mechanisms is that they are quite complicated and require a large number of parts, not only increasing the cost of manufacture of parts and assembly thereof but also increasing the possibility of problems due to improper assembly and due to wear or stressing of the parts.